In the discussion of the background that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicant expressly reserves the right to demonstrate that such structures and/or methods do not qualify as prior art.
Cemented carbide tips for soft cutting conditions generally have a flat bonding surface for joining to the body of the cutting bit. In tougher conditions, tips that utilize a “valve seat” bonding surface are preferred. Whether of the flat bottom design or the valve seat design, conventional tips for cutting bits suffer from using an excess of cemented carbide material and from difficulties during assembly.
The valve seat is formed by a solid projection of the material of the tip that is countersunk into the body of the cutting bit. While the valve seat design increases the bonding strength of the tip, it dramatically increases the volume of hard material required. Also, generally, the carbide in the valve seat does not contribute to the cutting performance of the cutting bit 2 because the valve seat is used for bonding and the cutting bit loses effectiveness well before the valve seat is exposed by wear processes.
Alignment during assembly and the bonding process can be an issue with conventional tip designs. Flat bottom tips are difficult to keep centered and valve seat tips tend to skew to one side. Because tips are often “misaligned”, operators are required to correct their orientation. This can be hazardous with hot braze coils in close proximity.